Storage controller and method for performing host access control in the host interface adapter

A method for controlling access by host computers to logical storage devices, the method comprising:

• performing a protocol to receive a request from a host computer to access a logical storage device;
• determining whether the host computer has access to the logical storage device;
• and
• causing the logical storage device to transfer data, if the host computer has access to the logical storage device based on said determining;
• wherein said performing the protocol and said determining are performed by an interface adapter, and said causing the logical storage device to transfer the data is performed by a microprocessor distinct from the interface adapter.

A storage router for providing virtual local storage on remote storage devices to devices, comprising:

• a buffer providing memory work space for the storage router;
• a first controller operable to connect to and interface with a first transport medium, operable to implement access controls for storage space on the storage devices;
• a second controller operable to connect to and interface with a second transport medium;
• and
• a supervisor unit coupled to the first controller, the second controller and the buffer, the supervisor unit operable to map between devices connected to the first transport medium and the storage devices and to process data in the buffer to interface between the first controller and the second controller to allow access from devices connected to the first transport medium to the storage devices using native low level, block protocols.

A method for mapping host-specific storage device identifiers to storage controller-specific storage device identifiers, the method comprising:

• receiving from a host computer a request to access one of a plurality of storage devices coupled to a storage controller, the request specifying an identifier of the host computer and an identifier of the one of the plurality of storage devices, wherein said receiving is performed by a host interface adapter of the storage controller;
• mapping a combination of the host computer identifier and the identifier of the one of the plurality of storage devices to a unique identifier used by a microprocessor of the storage controller to identify the one of the plurality of storage devices, wherein said mapping is performed by the host interface adapter;
• and
• providing the unique identifier to the microprocessor for processing the request, wherein said providing is performed by the host interface adapter.

A storage controller, comprising:

• a first microprocessor, for processing requests from a host computer to access one of a first set of logical storage devices coupled to the storage controller;
• a second microprocessor, for processing requests from said host computer to access one of a second set of logical storage devices coupled to the storage controller;
• and
• an interface adapter, coupled to said first and second microprocessors, for receiving said requests from said host computer, and for each of said requests determining whether said request specifies a logical storage device in said first set or said second set and providing said request to one of said first and second microprocessors based on said determining.

A storage router for providing virtual local storage on remote storage devices to devices, comprising:

• a buffer providing memory work space for the storage router;
• a first controller operable to connect to and interface with a first transport medium, operable to map between devices connected to the first transport medium and the storage devices;
• a second controller operable to connect to and interface with a second transport medium;
• and
• a supervisor unit coupled to the first controller, the second controller and the buffer, the supervisor unit operable to implement access controls for storage space on the storage devices and to process data in the buffer to interface between the first controller and the second controller to allow access from devices connected to the first transport medium to the storage devices using native low level, block protocols.